Re: Some thoughts about i/o priorities and throttling vacuum
Tom Lane <tgl@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Shridhar Daithankar <shridhar_daithankar@persistent.co.in>
Cc: Rod Taylor <rbt@rbt.ca>, Andrew Sullivan <andrew@libertyrms.info>, PostgreSQL Development <pgsql-hackers@postgresql.org>
Date: 2003-10-17T15:53:52Z
Lists: pgsql-hackers
Shridhar Daithankar <shridhar_daithankar@persistent.co.in> writes: > I agree. This seems to be the best way of dealing with things. Of course, > probably there are details we are missing here, but in general its good. Actually, this is all pure handwaving, because you are ignoring the need to remove index tuples. The existing VACUUM code amortizes index cleanup over as many tuples as it can. If you do partial vacuuming of tables then you are necessarily going to be expending more cycles (and I/O) per tuple, on average, to get rid of the index entries. It's not at all clear that there's any real win to be had in that direction. Perhaps it's a win, but you have no evidence on which to assert so. regards, tom lane